From Dr. Judith Curry’s Climate Etc.
There is a belief, by mostly among energy illiterates, increasing the level of wind and solar systems will get easier as more and more wind and solar systems are added to the grid.
Nothing could be further from the truth.
Think of expensive grid expansions and augmentations all over the US
Think of super-expensive grid-scale battery systems
Think of increasing capacities, MW, of existing power plants operating at variable outputs (less efficient, just as a car in urban areas) to counteract the increasingly larger up and down quantities of wind and solar outputs, 24/7/365
The challenge may be better understood as akin to pushing a huge rock, which is getting heavier and heavier, up a steeper and steeper slope, while the ground below is getting slicker and more unstable.
The drawbacks associated with increased penetration of wind and solar totally swamp any potential benefits that might be achieved through economies of scale, as Europe, which practiced an expensive, decades-long, wind/solar experiment, made possible by:
1) Huge subsidies,
2) Low interest rates,
3) Low inflation rates
4) Stable fuel and materials prices
5) A plentiful supply of low-cost oil, coal, and gas from Russia.
Items 2, 3, 4 and 5 have drastically changed, due to the predictable blowback of the EU’s hasty, vengeful, ill-considered sanctions to punish Russia, which will certainly caused a European recession, and may cause a worldwide recession.
The bulk power system has traditionally been strong and very robust, with a 99.98% reliability of service.
Adding minor percentages of wind and solar, say 5% of each, causes only minor problems.
Wind and solar rely on the electrical system for support, because they could not be admitted to the grid without it.
Wind and solar do not support the electrical system, as do almost all other generating plants tied to the grid.
The electrical system has a limited spare capacity to accommodate the variable outputs from wind and solar systems, which would displace some fossil fuel generation.
At low penetration of wind and solar, say 3 to 4%, one kWh of solar/wind may displace the CO2 of about 0.9 kWh of fossil fuel generation, due to minor system inefficiencies
At high penetration of wind and solar, say 16 to 18%, one kWh of wind/solar may displace the CO2 of only about 0.6 kWh of fossil fuel generation, due to major system inefficiencies.
Listed below are some reasons increasing the penetration levels of wind and solar will lead to rapidly increasing costs/kWh, due to system inefficiencies, as well as rapidly decreasing reliability.
1) Wind and solar do not readily supply essential reliability services. Conventional generation has characteristics that support the stabil...
If wind and solar were a larger percentage of the load on the grid, we see an erosion of these desirable characteristics.
Some argue, electronic simulation can serve to compensate for the loss of inertia of mass and spin characteristics, but it is costly and the results are inferior.
Previous writings going into detail on this topic include:
https://judithcurry.com/2015/05/07/transmission-planning-wind-and-s... https://judithcurry.com/2016/01/06/renewables-and-grid-reliability/
2 )Wind and solar are MOTHER-NATURE, WEATHER-DEPENDENT, intermittent resources, and their availability/output often does not match user needs, and does not support
Other power plants on the grid must counteract the intermittency of wind and solar, on a less than a minute-by-minute basis.
The greater the percentage of wind and solar on the grid, the greater the counteracting challenge, and the greater the cost for back-up plant capacity, MW, in case of wind/solar lulls, which can last 5 to 7 days, and may be followed by another wind/solar lull a few days later, likely before grid-scale battery systems would have been refilled.
Previous writings on this topic include:
- https://judithcurry.com/2014/12/11/all-megawatts-are-not-equal/
- https://judithcurry.com/2014/11/05/more-renewables-watch-out-for-th...
3) The successful, profitable performance of wind and solar installations is highly location specific.
Maps show the suitability and appropriateness of various locations for wind and solar power.
Other land use considerations make locations more or less suitable for wind and solar as well.
Current efforts to increase wind and solar make use of the most suitable sites.
The remaining sites would be less suitable.
As wind/solar installed capacity, MW, increase above current levels, the suitability of potential sites will decrease.
The posting below, co-written with Rud Istavan, provides some discussion of locational problems.
4) Wind and solar depend on materials which must be mined and their availability may be limited.
Increasing wind and solar systems, likely will increase materials costs and create supply problems.
European wind power is already seeing a fight over scarce materials.
5) As wind and solar generation increases, it will become more and more challenging, and costly, for other generating plants to subsidize their expansion.
It’s one thing to subsidize a small percentage of the generation mix, quite another thing to subsidize a major percentage.
- https://judithcurry.com/2015/04/21/what-should-renewables-pay-for-g...
- https://judithcurry.com/2015/02/09/clean-air-who-pays/
6) It takes a lot of energy to build wind and solar facilities.
Their operation and maintenance require a lot of energy, so-called self-consumption, which is needed 24/7/365, during all levels of output, including idling.
It is doubtful wind and solar can support themselves, I.e., provide load to the grid, and provide enough energy for building replacement systems of the same sort.
Additionally, if electric vehicles, and heat pumps, and electric ovens are added (as part of "electrifying"), the problem of providing reliable electricity service, 24/7/365, is further magnified. Think of transmission lines everywhere.
Green advocates want to eliminate gas appliances of residential and other buildings
Grid-scale battery system deployment, involves operating electricity losses; the total loss is about 18 to 20%, on an A-to-Z basis.
There are a class of concerns focusing on all the energy and resources consumed by wind and solar resources.
This is referred to as the energy density, or power density problem.
Here are a couple links (here, here, here and here) discussing these type concerns.
These concerns have been outside my area of experience.
I hope that readers may add more references in the comments.
7) Wind and solar make the study, control and operation of the power system more complicated and uncertain.
MOTHER-NATURE, WEATHER-DEPENDENT wind and solar are intermittent and more unpredictable for operators to contend with.
To maintain stability, good modeling is imperative.
Systems analysts need generating plant operating data, on a minute-to-minute basis
Getting good data for dispersed projects with many small elements, which might change during a project, and after installation, is much more challenging.
Lastly, system operators and systems analysts have decades of experience with large rotating machines, but not as much with wind and solar.
8) Widespread deployment of wind and solar would require power be transmitted across great distances (or you would need an unrealistic and incredible amount of battery storage)
Getting wind electricity from the GREAT PLAINS to population centers on the East and West Coast, involves long transmission lines.
Green advocates argue imbalances between load and generation from solar and wind resources can be overcome by drawing on resources from a broader geographical area.
This requires even greater needs for long power lines and a robust grid, which would require HVDC lines, as is widely practiced in much more compact Europe.
A high voltage DC line can transmit power great distances with much lower losses than AC lines.
As noted in item 1, solar and wind do not provide sufficient elements like inertia and spin to the electrical system
However, to utilize a high voltage DC line it is imperative to have a strong AC system receiving the power.
High voltage DC lines will not be the savior of a wind and solar based system.
While high levels of wind and solar penetration require a robust grid, their greater presence reduces the reliability of the grid.
The above is a formidable list of challenges.
How might they be overcome?
Not by economies of scale from increased wind and solar production.
First off, it’s hard to imagine that any economies of scale would allow these resources to leap the formidable challenges described above.
Secondly, it does not appear significant improvements in economies of scale are to be expected.
My perusal of the topic shows attempts to find economies of scale have failed.
Building more and more smaller units likely will not provide greater economies of scale, due to increased material costs.
Larger wind and solar facilities incur a class of costs not seen by smaller facilities.
Advocates of wind and solar argue, many smaller local projects provide more benefits (and jobs) than might be obtained from larger facilities.
Nuclear
Could nuclear energy be a piece of a lower carbon emission future?
Most certainly.
None of the above concerns apply to nuclear power, as France has proven for decades.
We could see cheaper costs from standardized nuclear facilities and reasonable regulations.
Hydro too works well with the power system.
Unfortunately, there are negligible to no potential locations to expand hydro generation.
Pumped storage is an option for storing energy, for later use; system operating losses are about 25 to 30%, on an A-to-Z basis.
It is way too soon to be envisioning a 100% renewable future with significant contributions from current wind and solar capabilities.
It is not a good strategy to support current “green” technologies and retire and prohibit conventional generation hoping that a miracle will occur when we need it.
Perhaps with the extensive deployment of nuclear power, carbon capture and other technologies, we might be able to approach a zero-carbon grid.
At best, current wind and solar technologies will play at most a small part in such a plan.
This is the first post in a series on The Penetration Problem
Part 1 Wind and Solar: The More You Do, The Harder it Gets
Part 2 Will the Inflation Reduction Act Cause a Blackout?
You need to be a member of Citizens' Task Force on Wind Power - Maine to add comments!
Join Citizens' Task Force on Wind Power - Maine